[Ethereum] better SingingInput message types

[hewigovens]

message EthereumTransaction {
    // all default values nonce, chain id, gas and etc
    // message
    oneof contract_oneof {
        Transfer transfer = 0; (value)
        ERC20Transfer transfer_erc20 = 1; (contract, value)
        ERC20Approve approve_erc20 (contract, value)
        ERC721Transfer transfer_erc721 = 2; (contract, token_type(3 types atm), token_id)
        SmartContract smart_contract = 3; (custom data) 
    }
}

[vikmeup]

Also review other blockchains to see if they follow the same pattern.

[optout21]

These blockchains are similar to Ethereum, could be applied to them as well:
Aeternity, Aion, Harmony, Nebulas

[optout21]

Ethereum protobuf has an optional payload, which is used for any contract call. The caller has to put together the encoded contract call message (using methods available in wallet-core).

[vikmeup]

These blockchains are similar to Ethereum, could be applied to them as well:
Aeternity, Aion, Harmony, Nebulas

Great, let's apply same standards across all chains to make sure they are consistent

[optout21]

ERC721Transfer transfer_erc721 = 2; (contract, token_type(3 types atm), token_id)

@hewigovens , I believe we use transferFrom method, with parameters from, to, and tokenId; no contract or token type. Is this OK?

function transferFrom(address _from, address _to, uint256 _tokenId) external payable;

[hewigovens]

yes we only use transferFrom

[vikmeup]

ERC721Transfer transfer_erc721 = 2; (contract, token_type(3 types atm), token_id)

@hewigovens , I believe we use transferFrom method, with parameters from, to, and tokenId; no contract or token type. Is this OK?

function transferFrom(address _from, address _to, uint256 _tokenId) external payable;

We use both.

Here is an example from Swift code, but initially implemented by OpenSea:

All the new collectibles are using new format, but there is legacy that we need to support. It would be great to specify either the version of type of transfer call.

enum NFTVersion: String {
    case version3 = "3.0"
    case version2 = "2.0"
    case version1 = "1.0"

    init(string: String) {
        self = NFTVersion(rawValue: string) ?? .version1
    }
}

enum NFTTransfer: Equatable {
    case transfer
    case transferFrom

    static func from(version: NFTVersion) -> NFTTransfer {
        switch version {
        case .version3:
            return .transferFrom
        case .version1, .version2:
            return .transfer
        }
    }
}

[optout21]

I checked on this, we use only method transferFrom from ERC721. In some cases ERC20.transfer is used with collectibles (with tokenID in value), but there is no transfer in ERC721.

EthereumTransactionService.swift

    static func data(for transaction: UnconfirmedTransaction, from: String) -> Data {

        case .token:
            return ERC20Encoder.encodeTransfer(to: to, tokens: transaction.value.magnitude)
        case .collectible(let collectible, _, let version):
            switch version {
            case .transferFrom:
                guard let from = AnyAddress(ethereum: from) else { return transaction.data ?? Data() }
                return ERC721Encoder.encodeTransferFrom(from: from, to: to, tokenId: collectible.tokenIDBigUInt)
            case .transfer:
                return ERC20Encoder.encodeTransfer(to: to, tokens: collectible.tokenIDBigUInt)
            }